Performance Truck: Dyno-Proven XS-425 Chevrolet Tahoe

Aftermarket Performance, with a Factory Warranty

How cool is this scenario? You sit down with your friendly neighborhood Chevrolet dealer to order a new Tahoe, and amid the usual post-deal jabbering about fabric guard and paint sealant, Mr. Salesperson says, "Are you interested in adding a supercharger, a three-inch suspension drop, 14-inch brakes with four piston calipers, and a set of 20-inch wheels?"

You heard that right.

At select Chevrolet dealers around the country, you can add go-fast parts to your new truck before you drive it off the lot--all of which will be covered by a real warranty that mirrors what your rig had from the factory.

These dealer-installed packages by Dyno-Proven Products can be as mild or as wild as the owner desires. For a complete Chevy Tahoe performance makeover, which Dyno-Proven calls its XS-425 package, you can expect to pay as much as $15,000 above the purchase price of the vehicle. The result is a 425-horse Tahoe, Suburban, or Avalanche that digs into a turn and stops like a sport sedan.

The rumbling exhaust note from the cat-back system first alerts you that you aren't driving a stock 5.3-liter Tahoe. Stick the shifter in drive, and the XS accelerates with authority and without the typical blower whine. This is because the CoolCharger isn't driven internally by gears but by a Kevlar belt. In the turns, the Dyno-Proven setup keeps the Tahoe level and understeer is all but gone--though the factory's steering feel remains. But perhaps the biggest improvement is in the brakes. The original brake pedal feel is replaced by firm, confidence-inspiring stopping power.

The heart of the XS-425 is its CoolCharger supercharger, which spins on ceramic bearings, eliminating the need for internal lubrication. The system runs so cool without oil that Dyno-Proven President Peter Bayer claims intercoolers are unnecessary in all but the hottest climates.

When supercharging a Flex-Fuel version of the Vortec 5300 engine, there's no need to swap the injectors: They can be instructed by a reprogrammed PCM (provided in the kit) to spray more fuel. The PCM corrects the air/fuel mix, changes the stock timing advance, and alters the transmissions shift points.

Dyno-Proven's suspension tweaks are equally thorough. Rather than achieving its three-inch drop with shorter rear springs, it uses custom-wound progressive springs that are the same height as the stock units. As the springs compress, they get stiffer, but during normal driving, the ride remains supple. Up front, instead of cranking down the torsion bars to lower the front end, the adjuster's hex pattern is altered to creates the same amount of tension as the stock adjuster.

Dyno-Proven's modifications will work on virtually any GM truck including the H2 with air suspension. In fact, a dealer-installed 500-horse engine and sport suspension kit for the Cadillac Escalade EXT and ESV are currently the company's best-sellers. All kits are 50-state legal.